Grinding wheel reciprocating mechanism



Feb- 16, 1954 P. A. GROBEY 2,669,072

GRINDING WHEEL RECIPROCATING MECHANISM Filed June 7, 1951 Patented Feb. 16, 1954 UNITED STATES PATENT OFFICE GRINDING WHEEL RECIPROCATING MECHANISM Application June 7, 1951, Serial N o. 230,349

9 Claims; 1

In my application for United States Letters Patent Serial No. 111,779 filed August 2 3, 1949, there is shown a grinding machine in which dur- Ving the grinding portion of the cycle, reciprocation of the grinding wheel axially is produced by interposing a member between a portion of the grinding wheel moving mechanism and a rotating eccentric in such a manner that the rotation of the eccentric produces the desired reciprocation of the grinding wheel.

'Ihe present invention has for an object to provide an' improved mechanism of the same general character but which provides for smoother operation and freedom from shocks, particularly when the member is being moved from and to operative position. For a complete understanding of this invention,l reference may be had to the accompanying drawings in which Figure 1 is a fragmentary end elevationv showing the member interposed between the eccentric and the wheel-moving mechanism.

Figure 2 is a View similar to Figure l but showing the member in full lines in inoperative position and in broken lines in a position intermediate the inoperative and operative positions. V'Figure 3 is a fragmentary eelvational View at right angles to Figure 1, parts being broken away and in section and broken lines indicating other positions of certain parts.

Figure 4 is a fragmentary top plan view of certain of the parts. Figure 5 is a detail vertical sectional view throughthe machine showing a portion of the main cam shaft.

Figure 6 is a fragmentary front elevation showing the connections of parts shown in Figure 5 to the grinding wheel head. A

Referring to Figure 6, a rotary work holder is supported on a bed 2 which also carriesa wheel head 3 having a directly connected motor driven grinding wheel 4. in position to operate upon work carried bythe rotary work head. The wheel' head is mounted for motion from and toward work .carried by the work head, and during the grinding operation is oscillated axially by mechanism which will later be described. The wheel head has a portion 5fdepending therefrom to which is secured a rod E which is also shown in Figure 5 and by which the axial position and. motion of the wheel head is controlled. This wheel head is normally urged to a retracted position as by a spring 'l (see Figure 5) bearing between extension 5 at one end and against a xed portionvofthe machine at 'the Cil The opposite end of the rod 6 carries a transverse pin 6a in the upper portion of an actuating lever Ii! fulcrumed at and having a cam follower |2 which rides upon a suitable cam (not shown), on a main cam shaft |3. This cam and cam follower provide for the normal retraction and advancing of the grinding wheel with respect to the work.

The rapid reciprocation of the grinding wheel during grinding operation is produced by the rotation of an eccentric carried by a rotating shaft 2| arranged at right angles to the rod 6 and oscillating in the direction of reciprocation of the wheel head 3 and this oscillatory member is effective for the purpose when a bar 22 slidably carried in a sleeve 23 is interposed between the eccentric 20 and a ring 24 journaled on a disk 25 carried by the pin 6a as shown in Figure 3. The lsleeve 23 is carried at the end of an arm 26 which is fulcrumed on a pivot 21 to which one end portion of an arm 28 is also fulcrumed. The arm 28 is journaled on a fixed shaft 29 and carries at one end a journaled roller 36. The opposite end portion of the arm 28 is slotted to receive the adjacent end of the arm 26 between its sides and is provided with an adjustable screw abutment 3| which may contact with an extension 32- of the arm 26 projecting on the opposite side of the pivot 2l from the sleeve 23.

v 'I 'he arms 2 6 and 28 are normally in alined extended relation with the .abutment 3| contacting the extension 32 and are so held as by a wire 'spring v35 secured at 36 to the arm 26 and having a laterally .turned extremity 31 (see Figure 4) overlying the arm 26. These arms 26 and 26 may, however, be moved relatively out of such extended relation against the action of the spring 35. The roller 36 may be engaged and lifted at certain times by a roller 40 (see Figure 5) carried. by an arm 4| extending laterally from a lever 42 whichis fulcrumed on the shaft 43 and which .carries acam roller 44 actuated by va cam 45. carried by the main cam shaft I3.

Y When the `grinding portion of the cycle is to be accomplished, the cam 45 acting upon the cam roller 44 rocks the arms 42 .and 4| in a direction to lift the cam roller 4|) and the cooperating roller 30 of the arm mechanism. This tends to lowern the arm 26 against the action of a coil spring (see Figure 1) which reacts between a fixed anchor 52 and a perforated lateral extension 53 on the arm 28. The lifting of the outer end of the arm 26 in this manner tends to rock the member 23 downwardly to bring the bar 22 in and ll the space between the eccentric 2|l`and lthe ring 24, and when' this hasoccurred the ro'- aeeaovc tation of the eccentric then acts to reciprocate the bar 22 causing the arm lll to be oscillated and producing corresponding reciprocation of the grinding wheel 4. The bar 22 is normally held pressed toward the eccentric 20 as by a coil spring 55. lf when the sleeve 23 is rocked downwardly to bring the bar 22 between the eccentric and the ring 24, the eccentric happens to be in angular position shown in broken lines in Figure 3, while the ring 24 is in the full line shown, the arm 2E is permitted to yield about its axis 21 and against the action of the spring 35 untilu such time as the eccentric moves to its opposite full line position shown in Figure. 3, whereupon the spring 35 completes the downward motion of' the sleeve 23, whereupon the eccentric. can take over control and oscillate the, rod. E. Thus the cam follower 4B can take its upper position regardless of the particular angular position that the eccentric 20 happens to be in and the eccentric will not take over control until there is room between it and the ring; 24. Thus the eccentric takes over the control and' reciprocatesthe grind ing wheel whenever called upon to do so with out shock.

At the end of the grinding portion of the cycle when the .arm 42 is allowed to drop the roller 4D, the spring 5) acts to return the bar 22 to inoperative raised position, `but this is permitted only when the eccentric 2t is in substantially its full line angular position shown in Figure 3 when no axial pressure is exerted against the bar 22. This is done by a spring latch mechanism shown best in Figures 3 and 4 which comprises a latch plate en carried by the end of a leaf spring 5l secured to a fixed bracket G2k as by means 0f screws 53. This latch mechanism has xed thereto a limit stop 64 which may bear against the outer face of a stop plate 55., this limiting the retraction of the stop 60 by eXure of the spring 5l. A longitudinally adjustable plate 6l having adjustable screw and slot connection at 68v to a bracket member 1U carried by the bar 22 projects beneath the lower edge of the latch plate 60. when the bar 22 is moved to its left hand position and the latch plate 60 and then obstructing and preventing lifting of the sleeve 23 to its inoperative position shown by dotted lines in Figure 3. The lower end of the latch plate 6D may be beveled as at 'il to ease the action between the latch plate and the member 61. A guide pin l2 carried by the bracket 1t and riding in a hole through an extension 'I3 from the sleeve 23 prevents turning of the bracket 'lil on the bar 22,.v

This resilient latch plate 60 lies in the vibrating path of the bar 22 ofl the vibrating device, excepty when this bar is in fully operative position, and cushions the action and .also serves with the spring 55 to keep the bar 22 in engagement with the eccentric as the sleeve 23 is being lowered to operative position, the entire construction cooperating so that there is no shock imparted to the grinding wheel when the reciprocating mechanism is placed in or out of operation.

From the foregoing description of an. embodiment of this invention it should be evident to those skilled in the art that various changes and modifications may be made without departing from its spirit or scope.

I claim:

1. In a grinding machine, an oscillatory support, a member connected to and movable with said support, a rotary grinding wheel carried by said support, an Voscillatory member spaced itl from said movable member, and a device mounted for motion from and to a position between said members and when in said position lling said space and transmitting vibratory motion from said oscillatory member through said device and said movable member to said grinding Wheel, said device comprising a pair of portions normally in alinement when said device is in said position and relatively yieldable laterally of the direction of vibration when being moved into said position, and means operatively connected to said portions tending to move said portions into such alinement and there hold them.

2. In a grinding machine, an oscillatory support, a member connected to and movable with said support, a rotary grinding wheel carried by said support, an oscillatory member spaced from said movable member, and a device mounted for motion from and to a position between said members and when `in said position lling said space and transmittingA vibratory motion from said oscillatory member through said device and said movable member to said grinding wheel, said device comprising a pair oi: arms pivoted together, means tending to hold said armsin extended angular relation, said arms being relatively movable out of such angular' relation in the direction of motion or said device into said position.

3. In a grinding machine, an` oscillatory sup port, a member connected to and movable with said support, a rotary grinding wheel carried by said supportJ an oscillatory member spaced g, fromr said movable member, and a devicel mounted for motion from and to a position. between said members and when in said position lling said space and transmittingY vibratory motion from said oscillatory rmember through said de f. vice. and said movable. member to said grinding moved into said position, yielding means tending to move said arms into such relatiom and a latch member interposed in the path of and preventing return of said device from said position except when said oscillatory member is in position furthest remoter from saidv movable member,

d. In a grinding machine, an oscillatory sup port, a member connected to and movable with said support, a rotary grinding wheel carried4 by said support, an oscillatory member spaced from saidr movable member,A and a device mounted for motion from andV to a position between said members and when in saidV position filling said space and transmitting vibratory motion from said oscillatory member through said device and said movable member to said grinding wheel, said device comprising a pair. of arms pivoted together and normally in extended angular relation when said device is in said position and relatively movable out of such relation in the direction of motion of said device when being movedl into said position, yielding means tending to move said arms into such relation, and a latch obstructing return of said device from said position except when said oscillatory member is in position fur thest remote from said movable member, said latch being yieldable in the direction of said vibratory motion and lying in the vibratory path of said device while said device is out of position to cushion said support.

v5, In a grinding machine, an oscillatory sup# port, a member connected to and movable with said support, a rotary grinding wheel carried by said support, an oscillatory member spaced from said movable member, a device mounted for motion from and to a position between said members and when in said position iilling said space and transmitting vibratory motion from said oscillatory member through said device and said movable member to said grinding wheel, and a member positioned to obstruct movement of said device from said position except when said oscillatory member is in position of oscillation furthest remote from said movable member.

6. In a grinding machine, an oscillatory support, a member connected to and movable with said support, a rotary grinding wheel carried by said support, an oscillatory member spaced from said movable member, a device mounted for motion from and to a position between said members and when in said position filling said space and transmitting vibratory motion from said oscillatory member through said device and said movable member to said grinding wheel, and a member position to obstruct movement of said device from said position except when said oscillatory member is in position of oscillation furthest remote from said movable member, said member being spring supported and engaging and cushioning said device While said device is being moved from and toward said position.

7. In a grinding machine, an oscillatory support, a member connected to and movable with said support, a rotary grinding wheel carried by said support, an oscillatory member spaced from said movable member, a device mounted for motion from and to a position between said members and when in said position filling said space and transmitting vibratory motion from said oscillatory member through said device and said movable member to said grinding wheel, and a member mounted to yield in said vibratory direction and along and in contact with which said device is moved toward and from said position.

8. In a grinding machine, an oscillatory support, a rotary grinding Wheel carried by said support, a rotary cam spaced from said support and having its rotational axis transverse to the direction of oscillation of said support, a laterally movable sleeve, a bar slidably mounted through said sleeve and interposable between said cam and support in position to transfer vibratory motion from said cam to said support, a pair of portions pivoted together and normally in extended relation, one of which portions carries said sleeve and the other of which portion is pivotally mounted to swing said sleeve into and out of position with said bar so interposed, said sleeve-carrying portion being yieldable about its pivot with the other of said portions when the other of said portions is moved to bring said sleeve into such position, and means operatively connected thereto for swinging said other portion to bring said bar into and out of said interposed position.

9. In a grinding machine, an oscillatory support, a rotary grinding wheel carried by said support, a rotary cam spaced from said support and having its rotational axis transverse to the direction of oscillation of said support, a laterally movable sleeve, a bar slidably mounted through said sleeve and interposable between said cam and support in position to transfer vibratory motion from said cam to said support, a pair of portions pivoted together and normally in extended relation, one of which portions carries said sleeve and the other of which portion is pivotally mounted to swing said sleeve into and out of position with said bar so interposed, said sleevecarrying portion being yieldable about its pivot with the other of said portions when the other of said portions is moved to bring said sleeve into such position, means operatively connected thereto for swinging said other portion to bring said bar into and out of said interposed position, an element carried by said bar, and a member yieldable in the direction of vibration of said bar and positioned adjacent to the path of motion of said element as said bar is swung and obstructing swing of said bar out of said position except when said bar is adjacent to one end of its path of vibration.

PAUL A. GROBEY.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,515,640 Wheaton Nov. 18, 1924 1,687,252 Laessker Oct. 9, 1928 1,704,130 I-Iunt Mar. 5, 1929 1,791,819 Kull Feb. 10, 1931 1,925,723 Long Sept. 5, 1933 

